Lee Seo-jin, born in Seoul in 1971, is one of Korean television's most reliable leading men, equally at home in period dramas and contemporary romance. He broke through in Damo (2003) and cemented his status with the sweeping historical epic Yi San (2007), where he played King Jeongjo. He returned to popular affection in Marriage Contract (2016) and later reinvented himself for a whole new audience through the Grandpas Over Flowers travel-variety franchise. His measured, quietly charismatic screen presence makes him a favorite for grown-up, emotionally serious roles.